Add WFS layer | ArcGIS Maps SDK for Kotlin

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Sample viewer app

Display a layer from a WFS service, requesting only features for the current extent.

Image of add WFS layer

Use case

WFS is an open standard with functionality similar to ArcGIS feature services. ArcGIS Maps SDK support for WFS allows you to interoperate with open systems, which are often used in inter-agency efforts, like those for disaster relief.

How to use the sample

Pan and zoom the map to see features within the current map extent. The WFS layer will be populated with features for the visible area whenever you stop navigating the map.

How it works

Create a WfsFeatureTable with a service URL and table name.
Set the feature request mode to ManualCache and axis order to NoSwap.
Create a FeatureLayer from the WFS feature table and add it to the map’s operational layers.
Listen for the onVisibleAreaChanged event to detect the visible map area, and for the onNavigationChanged event to detect when the user has stopped navigating.
When navigation ends, call populateFromService(...) on the WFS feature table, passing a query for the current visible extent.
Display a loading indicator while the WFS table is being populated.

Relevant API

FeatureLayer
MapView.onNavigationChanged
MapView.onVisibleAreaChanged
WfsFeatureTable
WfsFeatureTable.populateFromService

About the data

This sample uses a WFS service showing building footprints for downtown Seattle. For more information, see the ArcGIS Online item.

Sample Code

MainActivity.kt

AddWfsLayerViewModel.kt

AddWfsLayerScreen.kt

/* Copyright 2025 Esri
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */

package com.esri.arcgismaps.sample.addwfslayer

import android.os.Bundle
import androidx.activity.ComponentActivity
import androidx.activity.compose.setContent
import androidx.activity.enableEdgeToEdge
import androidx.compose.material3.MaterialTheme
import androidx.compose.material3.Surface
import androidx.compose.runtime.Composable
import com.arcgismaps.ApiKey
import com.arcgismaps.ArcGISEnvironment
import com.esri.arcgismaps.sample.addwfslayer.screens.AddWfsLayerScreen
import com.esri.arcgismaps.sample.sampleslib.theme.SampleAppTheme

class MainActivity : ComponentActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        // authentication with an API key or named user is
        // required to access basemaps and other location services
        ArcGISEnvironment.apiKey = ApiKey.create(BuildConfig.ACCESS_TOKEN)

        enableEdgeToEdge()
        setContent {
            SampleAppTheme {
                AddWfsLayerApp()
            }
        }
    }

    @Composable
    private fun AddWfsLayerApp() {
        Surface(color = MaterialTheme.colorScheme.background) {
            AddWfsLayerScreen(
                sampleName = getString(R.string.add_wfs_layer_app_name)
            )
        }
    }
}

/* Copyright 2025 Esri
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */

package com.esri.arcgismaps.sample.addwfslayer.components

import android.app.Application
import androidx.lifecycle.AndroidViewModel
import androidx.lifecycle.viewModelScope
import com.arcgismaps.Color
import com.arcgismaps.data.FeatureRequestMode
import com.arcgismaps.data.QueryParameters
import com.arcgismaps.data.SpatialRelationship.Intersects
import com.arcgismaps.data.WfsFeatureTable
import com.arcgismaps.geometry.Envelope
import com.arcgismaps.geometry.Polygon
import com.arcgismaps.geometry.SpatialReference
import com.arcgismaps.mapping.ArcGISMap
import com.arcgismaps.mapping.BasemapStyle
import com.arcgismaps.mapping.Viewpoint
import com.arcgismaps.mapping.layers.FeatureLayer
import com.arcgismaps.mapping.layers.OgcAxisOrder
import com.arcgismaps.mapping.symbology.SimpleLineSymbol
import com.arcgismaps.mapping.symbology.SimpleLineSymbolStyle
import com.arcgismaps.mapping.symbology.SimpleRenderer
import com.esri.arcgismaps.sample.sampleslib.components.MessageDialogViewModel
import kotlinx.coroutines.flow.MutableStateFlow
import kotlinx.coroutines.flow.StateFlow
import kotlinx.coroutines.flow.asStateFlow
import kotlinx.coroutines.launch

class AddWfsLayerViewModel(app: Application) : AndroidViewModel(app) {

    // Message dialog for error reporting
    val messageDialogVM = MessageDialogViewModel()

    // WFS service URL and table name
    private val wfsUrl = "https://dservices2.arcgis.com/ZQgQTuoyBrtmoGdP/arcgis/services/Seattle_Downtown_Features/WFSServer?service=wfs&request=getcapabilities"
    private val wfsTableName = "Seattle_Downtown_Features:Buildings"

    // Hold a reference to the WFS feature table for population
    private val wfsFeatureTable = WfsFeatureTable(url = wfsUrl, tableName = wfsTableName).apply {
        // Set manual cache mode so features are only requested when we call populateFromService
        featureRequestMode = FeatureRequestMode.ManualCache
        // Set axis order to NoSwap as required by the service
        axisOrder = OgcAxisOrder.NoSwap
    }
    // The ArcGISMap with the Seattle downtown initial viewpoint
    val arcGISMap = ArcGISMap(BasemapStyle.ArcGISTopographic).apply {
        // Envelope for Seattle downtown area (used for initial viewpoint)
        val seattleEnvelope = Envelope(
            xMin = -122.341581, yMin = 47.613758, xMax = -122.332662, yMax = 47.617207,
            spatialReference = SpatialReference.wgs84()
        )

        // FeatureLayer for displaying the WFS features
        val wfsFeatureLayer = FeatureLayer.createWithFeatureTable(wfsFeatureTable).apply {
            // Apply a simple red line renderer to building features
            renderer = SimpleRenderer(
                SimpleLineSymbol(
                    style = SimpleLineSymbolStyle.Solid,
                    color = Color.red,
                    width = 3f
                )
            )
        }
        initialViewpoint = Viewpoint(boundingGeometry = seattleEnvelope)
        operationalLayers.add(wfsFeatureLayer)
    }

    // Track if the WFS table is currently populating
    private val _isPopulating = MutableStateFlow(false)
    val isPopulating: StateFlow<Boolean> = _isPopulating.asStateFlow()


    // Used to track the latest visible area (Polygon)
    private var visibleArea: Polygon? = null

    init {
        // The FeatureLayer is the only operational layer
        val featureLayer = arcGISMap.operationalLayers.first() as FeatureLayer

        // Load the map and layer
        viewModelScope.launch {
            arcGISMap.load().onFailure { messageDialogVM.showMessageDialog(it) }
            featureLayer.load().onFailure { messageDialogVM.showMessageDialog(it) }
        }
    }

    /**
     * Called when the visible area changes. Used to update the visible area and trigger population if needed.
     */
    fun onVisibleAreaChanged(polygon: Polygon) {
        // Only populate on first visible area event
        if (visibleArea == null) {
            visibleArea = polygon
            populateWfsLayer(polygon.extent)
        } else {
            visibleArea = polygon
        }
    }

    /**
     * Called when navigation ends. Populates the WFS table for the current visible extent.
     */
    fun onNavigatingChanged(isNavigating: Boolean) {
        if (!isNavigating) {
            visibleArea?.extent?.let { populateWfsLayer(it) }
        }
    }

    /**
     * Populate the WFS feature table for the given extent.
     */
    private fun populateWfsLayer(extent: Envelope) {
        viewModelScope.launch {
            _isPopulating.value = true
            val query = QueryParameters().apply {
                geometry = extent
                spatialRelationship = Intersects
            }
            wfsFeatureTable.populateFromService(
                parameters = query,
                clearCache = false,
                outFields = emptyList()
            ).onFailure {
                messageDialogVM.showMessageDialog(it)
            }
            _isPopulating.value = false
        }
    }

}

/* Copyright 2025 Esri
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */

package com.esri.arcgismaps.sample.addwfslayer.screens

import androidx.compose.foundation.layout.Box
import androidx.compose.foundation.layout.Column
import androidx.compose.foundation.layout.fillMaxSize
import androidx.compose.foundation.layout.padding
import androidx.compose.material3.Scaffold
import androidx.compose.runtime.Composable
import androidx.compose.runtime.getValue
import androidx.compose.ui.Modifier
import androidx.lifecycle.compose.collectAsStateWithLifecycle
import androidx.lifecycle.viewmodel.compose.viewModel
import com.arcgismaps.geometry.Polygon
import com.arcgismaps.toolkit.geoviewcompose.MapView
import com.esri.arcgismaps.sample.addwfslayer.components.AddWfsLayerViewModel
import com.esri.arcgismaps.sample.sampleslib.components.LoadingDialog
import com.esri.arcgismaps.sample.sampleslib.components.MessageDialog
import com.esri.arcgismaps.sample.sampleslib.components.SampleTopAppBar

/**
 * Main screen layout for the AddWfsLayer sample app.
 */
@Composable
fun AddWfsLayerScreen(sampleName: String) {
    val mapViewModel: AddWfsLayerViewModel = viewModel()
    val isPopulating by mapViewModel.isPopulating.collectAsStateWithLifecycle()
    Scaffold(
        topBar = { SampleTopAppBar(title = sampleName) },
        content = { padding ->
            Box(modifier = Modifier
                .fillMaxSize()
                .padding(padding)) {
                Column(modifier = Modifier.fillMaxSize()) {
                    MapView(
                        modifier = Modifier
                            .fillMaxSize()
                            .weight(1f),
                        arcGISMap = mapViewModel.arcGISMap,
                        onVisibleAreaChanged = { polygon: Polygon ->
                            mapViewModel.onVisibleAreaChanged(polygon)
                        },
                        onNavigationChanged = { isNavigating ->
                            mapViewModel.onNavigatingChanged(isNavigating)
                        }
                    )
                }
                if (isPopulating) {
                    LoadingDialog(loadingMessage = "Populating features...")
                }
                mapViewModel.messageDialogVM.apply {
                    if (dialogStatus) {
                        MessageDialog(
                            title = messageTitle,
                            description = messageDescription,
                            onDismissRequest = ::dismissDialog
                        )
                    }
                }
            }
        }
    )
}